Sheet folding mechanism



y 1935- R. c. FLYNT 2,000,636

' SHEET FOLDING MECHANISM Filed July 20, 1934 4 Sheets-Sheet 1 EM! IIIWI H W i i lll May 7, 1935. I R. c

. FLYNT 2,000,636

SHEET FOLDING MECHANISM Filed July 20, 1934 4 Sheets-Sheet 2 y 1935- v R. c. FLVYNT 2,000,636

SHEET FOLDING MECHANISM Filed July 20,1934 4 Sheets-Sheet s May 7, 1935-' R. c. FLYNT 2,000,636

' SHEET FOLDING MECHANISM Filed July 20, 1934 4 Sheets-Sheet 4 Patented May 7, 1935 PATENT orrica 2,000,636 sneer FOLDING MECHANISM Robert C. Flynt, Winston-Salem, N. 0., assignor of two-fifths to Forrest G. Miles, Winston-- Salem, N. 0.

Application July 201 1934, SerlalNo. 736,239

12 Claims.

This invention relates to sheet folding mechanism and more particularly to sheet folding mechanism especially adapted for the folding of letters, circulars, advertising matter and the like,

although mechanism or apparatus according to my invention can be employed for other folding operations.

An object of the invention is to provide a mechanism of the character referred to which is of simple, compact and inexpensive construction, being adapted more especially for use in the handling of folding operations of comparatively small volume, that is, of such volume that hand folding would be uneconomical, but not sufficiently large to warrant the expense of the larger and more elaborate mechanism heretofore available. In attaining this object I provide a novel structure embodying folding elements, a feeding element and means cooperating with the feeding element for maintaining sheets in such position relative to the frame as to render possible the compact arrangement of the various parts of the apparatus and at the same time assuring efficient and rapid operation.

A further object is to provide a folding mechanism of the kind referred to and which is adapted to form two parallel folds in a sheet either in a manner to fold both end portions towards the same face of the central portion of the sheet as is customarily done with ordinary letters, or in such a way as to fold one end portion towards one face of the central portion and the other end portion towards the other face of the central portion so as to adapt the folded sheet, for example a letter, for use in connection with window envelopes. This may be accomplished, in accordance with the invention, by the provision of means for selectively feeding one or the other end portions of the sheet to the folding elements for the formation of the first fold, and means for controlling the operation of the folding elements in the formation of the second fold.

Another object is to provide a sheet folding apparatus of the type including buckling rolls and a feed roller with driving and timing mechanism which provides for the passage of sheets through the folding rolls unhindered by the feed roller, the latter, however, being adapted to engage the next sheet of the pile as soon as the sheet being folded is withdrawn from engagement with the feed roller, whereby successive sheets on the pile will follow each other through the folding rolls closely but separately and without danger of being folded together. In attaining this object, I prefer to provide a feed roller in constant engagement with the pile of sheets, and an over running drive device for the feed roller which permi'ts the latter to free-wheel when the sheet which it engages is being drawn through the folding rolls.

Other objects will become apparent from a reading of the following detail description, the appended claims and the accompanying drawings, in which:

Figure 1 is a perspective view of the sheet folding mechanism embodying my invention;

Figure 2 is a sectional view taken on the line 2-2 of Figure 3, some parts being shown in elevation;

Figure 3 is a sectional view taken on the line 3-3 of Figure 2;

Figure 4 is a sectional view taken on the line 44 of Figure 2;

Figure 5 is a detail sectional view taken on the line 5--5 of Figure 3 and drawn on an enlarged scale;

Figures 6 to 11 inclusive are diagrammatic views of folding rolls, a feed roller, and a sheet guide in position for forming a single fold, and graphically illustrating the operation and effect of an over running drive for the feed roller;

Figures 12, 13 and 14 are diagrammatic views similar to Figures 6 to 11 but showing the sheet guide so positioned as to effect formation of two parallel folds in each sheet, the end portions of the sheets being folded inwardly towards the same face or surface of the central portions;

Figure 15 is a fragmentary view in side elevation and showing the feed roller positioned so as to effect formation of parallel folds, one end portion of the sheet being folded towards one face of the central portion, and the other end portion being folded towards the other face of said central portion; and

Figures 16, 17 and 18 are diagrammatic views illustrating the operation of the mechanism as set up in Figure 15.

The preferred embodiment of the invention shown in the drawings for the purposes of illustration includes a frame A which conveniently 4 may comprise side members I and 2, bottom cross pieces 3 and 4, top cross pieces 5 and 6 and an elevated sheet-receiving platform I, which latter is preferably provided with receiving skids 8. In the form shown the frame includes also bearing bracket members 9 and I0 connected to the side 2 and joined at their top ends by a cross piece II, and bearing bracket members l2 and i3 connected to the side I and joined at their top ends by a crosspiece M. An upright supporting memher I5 is mounted on the cross piece 5 and serves to support a sheet guide table l6, the purpose of wliich will be described later. The parts thus far described may be, and in the form shown are, secured together so as to be relatively immovable and thus to constitute a rigid frame.

Folding mechanism generally designated B includes two parallel and peripherally engaged folding rolls l1 and I9 mounted with their axesof trunnions 25 journalled in blocks 26 mounted for vertical sliding movements in slots 21 in the brackets HI and I3. Springs 26 interposed between the trunnions 25 and the trunnions 22 of the roll l8 urge the roll 24 into engagement with the roll I 6. The rolls may-be formed of, or surfaced with, a suitable yielding material such as cork, rubber or the like.

Means, in the form shown a support 29, is provided under the rolls I1 and I8 for holding a pile 30 of sheets to be folded, the support being urged upwardly towards the rolls by means of leaf springs 3| secured to the cross pieces 3 and 4 and engaging the bottom of the support. A cord 32 connected to the support as at 33 and to the frame as at 34 and 35 limits endwise movement of the support without danger of binding which might be caused by fixed guides. Upward movement of the support and pile of sheets is limited by engagement of the latter with a feed roller 36 and one or the other of the frame top cross pieces 5 and 6 depending upon which of two positions the feed roller is mounted in. A sheetpositioning abutment 29 is adapted to be secured to the platform 29 in adjusted position by means of a bolt 29 passing through the abutment and a slot 29 in the platform and having a wing nut 29' on its lower end. By adjusting the position of the abutment 29 it is possible to position the sheets in such relation to the folding rolls as to cause the folds to be formed at the desired part of the sheet. Latch elements 29 and 29 on the frame and platform are adapted to cooperate for maintaining the platform in retracted position to facilitate positioning of thesheets. A hump 29 extending across the platform 29 deforms the sheets upwardly to facilitate formation of the commencement of a fold by buckling.

The feed roller 36 is secured to a shaft 3! by means of set screws 36, the shaft being adapted to be journalled in bearings 39 at the left of the roll IT, or in bearings 40-40 at the right of the roll l8, as viewed in Figures 1 and 2. The arrangement is such that when the set screws 36 are loosened the shaft 31 may be withdrawn from one pair of bearings and the feed roller and shaft assembly then set up for rotation in the other set of bearings, the purpose of shifting the feed roller assembly being explained hereinafter. The feed roller may be formed of or surfaced with material such as rubber, having a tendency to grip the sheets frictionally and preferably the periphery of the roller is serrated in order to provide for a more complete gripping action and more effective feeding.

Take-off rollers 4| mounted on a shaft 42 journalled in bearings 43 are disposed in position to receive folded sheets emerging from between the 3 rolls l6 and 24, and to move the folded sheets on to the skids I. The take-off rollers also may be serrated in order to more surely grip and feed the sheets.

Preferably the folding rolls l1, l8 and 24, the feed roller 36 and the take-oil. rollers 4| are driven by common operating means such as a crank 44 secured to a gear 45 mounted for rotation on a stub shaft 46. Motion of the crank and gear 45 is transmitted to the folding rolls l1, l8 and 24 through the medium of a gear 41 secured to the roll l8 and meshing with the gear 45. Belts 46 and 49 pass around pulleys 50 and 5| secured to the crank 44 and respectively around a pulley 52 secured to the shaft 42 of the take-off rollers 4| .and a pulley 53 loosely mounted on the shaft 31 of the feed roller 36. The pulley 53 is mounted loosely on the shaft 31 in order to provide a free wheeling or over running drive for the feed roller, thus permitting sheets which are gripped by the folding rolls I1 and I8 to be withdrawn from under the feed roller-36 without the latters exerting a drag on the sheets. The drive from the pulley to the feed roller shaft is effected by means of a pin 54 fixed to the pulley and a pin 55-flxed to the shaft and adapted to be engaged by the pin 54 when the pulley is rotated.

In operation, the feed roller 36 rotates in a clockwise direction as viewed in Figure 2 and buckles the top sheet 3|) so as to form the com- 'mencement of a fold at 3|] and to raise the buckled portion into contact with the rolls l1 and I6 which are rotating in the direction of the arrows in Figure 2. The sheet is then passed between the rolls l1 and 8 and the fold emerges vertically as shown in Figure 7. In some cases it is desirable to form only one fold in-the sheet and for accomplishing this I provide guide means preferably comprising a sheet metal member 56 secured to the upright supporting member |5 by means of a. bolt 51 and wing nut 58 and having a guide portion 59 disposed above the line of engagement of the rolls l1 and I8 and curved in a manner to deflect the folded sheet between the rolls l8 and 24 which will act merely as feeding or discharging rollers delivering the once-folded sheet to the take-off rollers 4| which, in turn, deliver the sheet to the skids 8 on the platform I. Retaining rods 60 adjustably mounted in slots 6| in the platform I prevent the folded sheets from fallingofi. the end of the platform. I

A weight 60 may be placed on top of the folded sheets to prevent them from bulging and stacking up too high? In other cases it may be desired to form two parallel folds in the sheets. This requires that the sheet be routed through the folding rolls differently; and in accordance with my invention the change in routing is effected by positioning a different guide portion 62 of the member 56 in the path of sheets emerging from the rolls. I1 and I8. The guide portion 62 is curved, as shown in Figures 12, 13 and 14 so as to deflect the emerging once-folded sheet away from the rolls l8 and 24, and under the guide member 56 until the formed fold engages an abutment 63 between the guide member 56 and the guide table |6 after which a second fold forms at 30 and the twice folded sheet passes between the rolls l8 and 24 as shown in Figure 13. Thus, through the provision of interchangeable guide means, the sheets may be routed so as to form either a single fold or two parallel folds. For convenience and simplicity the guide portions 59 and i2 are both formed on the single element 55 which need only be reversed in order to provide for the required change in routing of the sheet. The abutment 53 is clamped in adjusted position by means .of the wing nut 58, being adjustable towards or away from the rolls I 8 and 24 for varying the position of the second fold 30.

Apparatus in accordance with my invention is adapted to be adjusted to adapt it for the formation of different kinds of folds, depending upon thesize of the sheet, the nature of printed matter thereon, or other factors. In order that the cooperation of the various parts may be more fully understood, complete cycles of operation will be described for different adjusted positions.

When it is desired to form a single fold in each of the sheets, as by folding the sheets transversely in half, the apparatus will be set up as shown in Figures 1, 2, 3, 4 and 6 to 11 inclusive, the feed roller 38 being mounted to the right of the folding roll I! and the guide portion 59 being disposed above the line of contact of the folding rolls l1 and I8. The springs 31 will urge the platform 29 upwardly, movement of the latter and the pile 30 of sheets being limited by engagement of the latter with the cross piece and the feed roller 36 so as to beheld out of contact with the folding rolls l1 and I8.

Before the crank 44 is turned in order to start operation, the pin 55 on the loose pulley 53 and the pin 54 on the feed roller'shaft 31 will be in the positions shown in Fig. 6. When the crank 44 is turned in a counter clockwise direction the pulley 53, folding roll l8 and take-01f rollers 41 will be driven in a clockwise direction. The pin 55 on the pulley 53 being in engagement with the pin 54 on the shaft 31 will drive the feed roller causing the latter to feed the right hand end portion of the top sheet 30 toward the left so as to buckle the sheet bringing itinto contact with the rollers I: and I8 by which the sheet will be grasped and a fold 30" formed as the sheet passes through the rolls. The position of the pins 54 and 55 at the time the fold 30 is formed is shown in Figure 7. The rolls I! and 18 being moved at a rate to feed the sheet faster than the feed roller 36 will draw the sheet along under the feed roll causing the latter to run in advance of the pulley 53, there being no drag exerted by the feed roller. The positions of the parts just as the fold 30 emergesfrom between the rolls i1 and I8 and just before the right hand end of the top sheet is withdrawn from under the feed roller are shown in Figure 8, wherein the feed roller 36 has run about 90 in advance of the pulley 53. The fold 30 upon emerging from between the rolls I1 and It will engage the guide portion 59 which will deflect it between the rolls l8 and 24 as indicated in Figures 8 and 9. By the time the fold 30* has actually entered between the rolls i8 and 24 the top sheet will have been withdrawn from under the feed roller 35 which will then contact the next lower sheet. The sheet 30 will then be fed through the feed rolls and onto the takeoff rollers 4|. While the sheet is being fed from the position shown in Figure 9 to that shown in Figure the feed roller will remain stationary because of the lead of the pin 54 over the pin 55. Thus the sheet next below the sheet 30* will not be fed to the folding rollers until the top sheet 30 is well on its way through the folding rolls. By the time the sheet 30' reaches the position-sho inl 'igurelothepinllouthepulley 53 will he, emovedupinto engagement withthe pin 54 onthe feed roller shaft and rotation of the feed roller will be resumed causing the sheet next belowthesheet 3|- tobe buckled and fed totherollsl'landliasshowninl 'iguren. By virtue of the free wheeling drive of the feed 'rollerandthetimingofthevariousrollsand rollers the sheets will be caused to follow each other closely through the folding rolls without danger of being folded together. As the sheets emerge from between the rolls II and 24 they will be delivered to the take-off rollers 4| which will move them toward the right and dispose them one under the other on the skids 8.

When it is desired to form two parallel folds in a sheet, both end portions of the sheet being folded inwardly toward the same surface or face of the central portion, the mechanism will be set up as shown in Figures 1, 2, 3 and 4 with the exception that the guide portion 52 of the guide member 55 will be disposedover the line of contact of the rolls l1 and II and the pile II will be shifted toward the right so as to bring the line of the first fold to be formed approximately under the line of contact of the rolls l1 and II. Figures 12, 13 and 14 show diagrammatically the path of the sheet through the folding rolls when the machine is set up in this manner. The operation of the feed roller in timed relation to the folding rolls will be similar to that described above. The top sheet 30 will be buckled as previously described, but the line of buckling and hence the line of the first fold will be disposed adjacent the left hand end of the sheet. The sheet with the first fold therein will then pass between the rolls I1 and I8 and will engage the guide portion 62 which will deflect the fold 30 toward the left into engagement with the abutment 63 as shown in Figure 13. Further rotation of the folding rolls would cause a second fold 3|! to be formed as shown in Figure 13. The rolls l8 and 24 will then grip the twice folded sheet and feed it onto the take-oil? rollers 4|, Figure 14 showing the twice folded sheet passing between the rolls l8 and 24. It will be understood that in some cases it may be desired to fold the sheets in half by means of a single fold as described in connection with the diagrammatic Figures 6 to 11, inclusive, and then to reset the apparatus and run the sheets through the rolls with the first formed fold transverse to the roll axes so as to form two folds transverse to the first halving fold.

The folds formed in the manner described with reference to Figures 12, 13 and 14 are suitable for folding ordinary business letters or the like for insertion in closed opaque envelopes, all of the printed matter being folded in so as not to be visible on the folded sheet. If, however, it is desired that one of the three sections of the sheet formed by the folds be on the outside of the folded sheet, for example, to display the address at the top of the letter through the window of a window envelope, the machine will be set up as shown in Figure 15 and the passage of the sheets pile of sheets with their right hand end portions disposed under the rolls I! and It. When the crank 44 is rotated in a counter clockwise direction the feed roller 36 will buckle the top sheet 30 and feed it inwardly towardthe right, the buckled portion being gripped by the folding rolls i1 and i8 and fed upwardly therethrough as shown in Figure 16. The first fold 38 will engage the guide portion 82 which will deflect it toward the left into engagement with the abutment 6! at which time the rolls l8 and 24 will grip the trailing portion of the sheet and form a second fold 30 and willfeed the twice folded sheet onto the take-oil rolls. It will be clear from an inspectionof Figures 17 and 18 that in the formation of the first fold 3B" the adiacent end portion of the sheet will be folded against one face of the central portion whereas in the formation of the second fold ll the end portion adjacent this fold will be folded against the 'opposite face of the central portion of the sheet. By folding the sheet in this manner the address can be exposed on one end portion and at the same time all other printed matter folded in so as not to be exposed.

The position on the sheets at which the first fold is formed is controlled by the initial positioning of the sheets on the platform 20 and the positioning. on the sheets at which the second fold is formed may be varied by shifting the ad- Justable abutment 63 towards or from the rolls l8 and 24.

From the foregoing it is apparent that because of the novel arrangement and relative disposition of the parts comprising my improved sheet folding mechanism, and the adaptability of the parts to selective arrangement, I am able with a single compact mechanism to fold sheets in any of the different ways usually required. Although the mechanism is of simple and inexpensive construction it has been found to function rapidly and with reliability, the over running drive for the feed roller preventing the folding of two or more sheets together.

The mechanism disclosed herein is a practical and the at present preferred embodiment of the invention but changes may be made in the specific construction and relative arrangement of the parts without departing from the invention as defined in the claims.

I claim:

1. In sheet folding mechanism, the combination of an element for forming folds and feeding a folded sheet; a roller for effecting commencement of a fold in a sheet and delivering said sheet to said fold-forming and feeding element; a common driving means for said fold-forming and feeding element and said roller; and driving connections between said driving means and said.

roller including an over running drive device. said driving connections being such as at all times to provide uninterrupted driving connection except for said over running drive device.

2. In sheet folding mechanism, the combination of a fold-forming and feeding element; means for supporting a pile of sheets; a roller in constant contact with said pile of sheets and adapted to effect commencement of a fold in a sheet and to deliver said sheet to said fold-forming and feeding element; driving means; and drive connections between said driving means and said roller and fold-forming and feeding element, the drive connections between said driving means and said roller including a shaft connected to the roller, :1. wheel mounted for rotation relatively and coaxially with respect to said shaft, a single abutment on said shaft, and a single cooperating abutment on saidwheel adapted to engage said shaft abutment to effect driving connection between the wheel and the shaft.

3. In sheet folding mechanism, the combination of a fold-forming and feeding element; means for supporting a pile of sheets; a roller in constant contact with said pile of sheets and adapted to effect commencement of a fold in a sheet and to deliver said sheet to said fold-forming and feeding element; means for driving said folding and feeding element and said roller at such rates that the former feeds the sheet faster than the latter; and driving connections between said driving means and said roller including an over running drive device, said driving connections being such as at all times to provide uninterrupted driving connection except for said over running drive device.

4. In sheet folding mechanism, the combination of a plurality of fold-forming rollers; a feed roller adapted to start a fold in a sheet and deliver said sheet to the fold-forming rollers; driving means for all of said rollers; and driving connections between said driving means and said roller including an over running drive device, said driving connections being such as at all times to provide uninterrupted driving connection except for said over running drive device.

5. In sheet folding mechanism, the combination of fold-fomiing rollers, means for supporting a pile of sheets, a feed roller in constant contact with said pile and adapted to deliver individual sheets to said fold-forming rollers; driving means for all said rollers adapted to drive them at such relative speedsthat the fold-forming rollers move a sheet more rapidly than the feed roller; and driving connections between said driving means and said roller including an over running drive device, said driving connections being such as at all times to provide uninterrupted driv-- ing connection except for said over running drive device, the drive being so timed that when a sheet is in engagement with the fold-forming rollers it will cause the feed roller to free-wheel until the sheet has been withdrawn from contact with said feed roller, the latter then immediately engaging the next sheet of the pile.

6. Insheet folding mechanism, the combination of folding rolls adapted to form two parallel folds in a sheet; means for holding a pile of sheets adjacent to but out of contact with said rolls and with two opposite edges of the pile disposed parallel to the axes of the folding rollers and respectively on opposite sides of the axes; a feed roller adapted to engage the sheet of said pile nearest said folding rolls and to deliver an intermediate portion of said sheet to said folding rolls; and means for selectively mounting said feed roller in either of two positions so as to engage said sheet and feed it selectively from either of said two opposite pile edges.

7. In sheet folding mechanism, the combination of folding rolls adapted to form two parallel folds in a sheet; means for holding a pile of sheets adjacent to but out of contact with said rolls and with two opposite edges of the pile disposed parallel to the axes of the folding rollers; a feed roller adapted to engage the sheet of said pile nearest of said separate hearings, and thus being adapted to feed sheets towards said folding rollers from either of said opposite pile edges.

8. In sheet folding mechanism, the combination of folding rolls adapted to form two parallel folds in a sheet; means for holding a pile of sheets.

adjacent to but out of contact with said rolls and with two opposite edges of the pile disposed parallel to the axes of the folding rollers; a feed roller adapted to engage the sheet of said pile nearest said folding rolls and to deliver an intermediate portion of said sheet to said folding rolls; separate bearings for said feed roller located on opposite sides of said folding rolls, the feed roller being adapted to be mounted for rotation in either of said separate bearings, and thus being adapted to feed sheets towards said folding rollers from either of said opposite pile edges; and means for driving said folding rolls and said feed roller including a drive connection adapted to drive the feed roller clockwise or counter-clockwise depending upon which of said bearings it is mounted in.

9. In sheet folding mechanism the combination of two folding rolls having peripheral engagement with each other and having parallel axes substantially in a horizontal plane; a third roll disposed above and peripherally contacting one of said first two rolls; a sheet support mounted under said first two rolls; means for urging said support and a pile of sheets supported thereon upwards towards said first two rolls; and means for engaging the top sheet of the pile and limiting movement of the support and the pile so as to prevent the piles being pressed against said first two rolls, said means including a feed roller which when rotated buckles the top sheet and moves it into engagement with said first two rolls.

10. In sheet folding mechanism the combination of two folding rolls having peripheral engagement with each other and having parallel axes substantially in a horizontal plane; a sheet support mounted under said rolls; means for urging said support and a pile of sheets supported thereon upwards towards said rolls; and means for engaging the top sheet of the pile and limiting movement of the support and the pile so as to prevent the piles being pressed against said rolls, said means including a feed roller which when rotated buckles the top sheet and moves it into engagement with said rolls.

11. In sheet folding mechanism the combination of two folding rolls having peripheral engagement with each other and having parallel axes substantially in a horizontal plane; a third roll disposed above and peripherally contacting one of said first two rolls; a sheet support mounted under said first two rolls; means for urging said support and a pile of sheets supported thereon upwards towards said first two rolls; means for driving said rollers; means for guiding a sheet passed between said first two rollers between the third roll and the roll with which it peripherally contacts; a take-off roller disposed in position to receive sheets discharged from between said last mentioned rolls and to movesaid sheets away from said rolls; and means for driving said take-off roller.

12. In sheet folding mechanism the combination of two folding rolls having peripheral engagement with each other and having parallel axes substantially in a horizontal plane; a sheet support mounted under said rolls; means for urging said support and a pile of sheets supported thereon upwards towards said rolls; and means for engaging the top sheet of the pile and limiting movement of the support and the pile so as to prevent the piles being pressed against said rolls, said means including a fixed element -on one side of said rolls, and a feed roller on the-opposite side of said rolls and which when rotated buckles the top sheet and moves it into engagement with said rolls.

ROBERT C. FLYNT. 

